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UNITED  STATES  DEPARTMENT  OF  AGRICULTURE 
SYLLABUS  11  (Revised) 

Contribution  from  the  States  Relation*  Service 
A.  C.  TRUE,  Director 


Washington,  D.  C. 


March  2, 1918 


ILLUSTRATED  LECTURE  ON 
WHEAT  CULTURE 


By 

J,  I.  SCHULTE,  Assistant  Agriculturist,  Office 
of  Experiment  Stations,  States  Relations  Service 


CONTENTS 


Page 

Introduction    ............  1 

History I 

Growth  and  Requirements  *    »    .    ,  ' ,    .  2 

Description  of  the  Plant s    .  3 

Composition    ......„.,,.  6 

Types  and  Varieties    ,    ,    , 6 

Improvement  of  Varieties    ,..,..  7 

Geographical  Distribution <  8 

Choice  and  Preparation  of  the  Soil  .    .    .  8 

Manuring    .,..., 9 


Page 

Seed  and  Seeding 11 

Crop  Rotations    ..........  12 

Irrigation  and  Rainfall     .......  13 

Wheat  Growing  In  the  Seraiarid  Regions  14 

Harvesting 15 

Storage 16 

The  Uses  of  Wheat      ........  16 

Diseases  and  Insect  Enemies  .....  16 

Production,  Yields,  and  Statistics    ...  17 

Appendix 19 


WASHINGTON 
GOVERNMENT  PRINTING  OFFICE 

191$ 


U.  S.  DEPARTMENT  OF  AGRICULURE, 

STATES  RELATIONS  SERVICE, 
A.  C.  TRUE,  Director. 


SYLLABUS  11— ILLUSTRATED  LECTURE  ON 
WHEAT  CULTURE.1 

By  J.  I.  SCHULTE,  Assistant  Agriculturist,  Office  of  Experiment  Stations, 
States  Relations  Service. 

INTRODUCTION. 

Wheat  is  the  world's  choicest  bread  crop  and  the  source  of  View- 
one  of  the  principal  foods  of  the  most  progressive  and  intelli- 
gent nations.  The  United  States  is  the  leading  wheat-produc- 
ing country  of  the  world,  and  it  is  of  the  greatest  importance 
that  its  rank  in  this  respect  be  maintained.  Year  by  year  the 
requirements  are  growing,  and,  as  production  is  not  increasing 
at  the  same  rate  as  consumption  and  exportation,  wheat  cul- 
ture should  be  placed  on  a  more  efficient  basis.  Earlier  in 
our  history  the  total  yield  was  increased  by  bringing  new  lands 
under  cultivation  and  devoting  them  largely  to  wheat  culture, 
but  such  lands  are  no  longer  available  in  sufficient  area  to  be 
of  great  significance  in  this  connection  and  attention  must  now 
be  given  to  increasing  the  production  of  the  country  by  other 
ways  and  means.  .  The  average  yield  per  acre  at  present  is  only 
about  15  bushels,  whereas  in  some  European  countries  it  is 
double  this  quantity,  and  even  more.  With  the  average  yield 
per  acre  of  England  this  country  would  be  capable  of  more 
than  doubling  its  annual  total  production.  The  wheat  soils 
of  this  country  can  be  made  as  productive  as  those  of  other 
countries,  and  to  bring  this  about  on  a  profitable  basis  is  one  of 
the  important  problems  of  American  agriculture. 

HISTORY. 

Wheat  is  probably  a  native  of  western  Asia,  and  its  cultiva- 
tion is  very  ancient.     The  Chinese  are  said  to  have  grown 

1  This  syllabus  has  been  prepared  by  direct  cooperation  between  the  author,  J.  I.  Schulte,  as 
regards  subject  matter,  and  J.  M.  Stedman,  Farmers'  Institute  Specialist  of  the  States  Rela- 
tions Service,  as  regards  pedagogical  form.  It  is  designed  to  aid  farmers'  institute  and  other 
extension  lecturers  in  presenting  this  subject  before  popular  audiences.  The  syllabus  is  illus- 
trated with  46  lantern  slides.  The  numbers  in  the  margins  of  the  pages  refer  to  the  lantern 
slides  as  listed  in  the  Appendix. 

27849°— 18 1 

444101 


tj  &j$Qft'  years  before  the  Christian  era,  and  the  plant  is 
•  .-  ,.:als,o.Jmo.wn  by  different  names  in  most  ancient  languages. 
:*:T  "jS.1  i-*.'FuriiifenAQr6,-.the  grain  itself  has  been  found  in  prehistoric 
works  and  monuments.     So  far  as  known,  the  crop  was  not 
grown  in  America  before  the  discovery  by  Columbus. 

GROWTH  AND   REQUIREMENTS. 

Wheat  requires  moisture,  air,  light,  heat,  and  plant  food  for 
its  development.  Most  of  these  factors  are  more  or  less  under 
control.  Moisture  under  certain  conditions  is  regulated  by 
cultivation,  drainage,  and  irrigation.  Air  is  admitted  into  the 
soil  by  means  of  drainage  and  tillage.  Light  has  free  access  to 
the  parts  of  the  plants  that  require  it.  The  degree  of  heat 
necessary  for  germination  and  growth  is  influenced  to  a  certain 
extent  by  the  choice  of  the  season  for  planting  and  by  cultiva- 
tion to  reduce  evaporation,  and  plant  food  is  supplied  from  the 
quantity  of  nutritive  elements  naturally  stored  in  the  soil  and 
maintained  and  replenished  by  the  different  methods  of  soil 
fertilization  and  management. 

The  plant  body  is  composed  of  cells  containing  during  their 
life  a  substance  called  protoplasm,  having  the  remarkable 
power  of  changing  the  foods  taken  up  by  the  plant  into  the 
substances  used  in  building  up  the  cell  wall  and  at  the  same 
time  providing  for  those  entering  into  its  own  composition. 

Two  general  groups  of  substances  are  formed  within  the 
plant,  namely,  the  carbohydrates  and  the  proteids.  The  car- 
bohydrates, of  which  starch  and  sugar  are  good  examples,  are 
composed  of  carbon,  hydrogen,  and  oxygen;  and  the  proteids, 
in  addition  to  these  three  elements,  contain  nitrogen  and  some- 
times also  sulphur  and  phosphorus.  Much  of  this  elaborated 
soluble  material  is  used  in  the  nourishment  and  growth  of  the 
plant.  The  surplus  is  carried  to  the  storage  organs,  such  as 
the  bulbs,  roots,  fruits,  seeds,  etc.,  where  in  some  cases  it  is 
deposited  in  solid  form.  In  wheat  and  other  grains  the  stor- 
age organ  is  the  kernel. 

By  growth  of  the  plant  we  understand  an  increase  in  the 
number  of  cells  in  the  plant  structure.  The  building  up  of 
organic  substances,  such  as  carbohydrates  and  proteids,  from 
the  elements  of  organic  and  inorganic  material,  is  the  most 
important  part  of  the  process.  Water  taken  up  by  the  roots 
moves  within  the  plant  through  the  ducts  and  the  cell  walls, 
according  to  the  laws  of  capillarity,  osmosis,  and  diffusion,  and 
passes  out  through  the  leaves. 

The  water,  on  entering  the  roots,  carries  inorganic  matter 
in  solution,  and  gases,  especially  carbon  dioxid,  are  taken  into 


the  leaves  from  the  air.  As  these  substances  are  subjected  in  Vlew 
the  leaves  to  the  combined  action  of  light  and  chlorophyll,  the 
formation  of  the  carbohydrates  takes  place.  Less  is  known 
about  the  formation  of  proteids^  but  it  is  believed  that  they  are 
formed  in  the  leaves  much  in  the  same  way  as  the  carbohy- 
drates, although  light  does  not  act  so  directly  in  their  produc- 
tion. The  proteids  are  produced  in  much  smaller  quantities 
than  carbohydrates,  but  they  are  nevertheless  of  greatest 
importance  to  the  life  of  the  plant. 

DESCRIPTION   OF  THE  PLANT. 

GERMINATION. 

The  vegetative  life  of  the  plant  begins  with  the  germina- 
tion of  the  seed,  and  for  this  process  moisture,  air,  and  the 
proper  temperature,  all  operative  at  the  same  time,  are  re- 
quired. The  parts  of  the  wheat  kernel  of  prime  importance 
n  germination  are  the  embryo,  or  germ,  which  develops  to 
form  the  young  plant,  and  the  endosperm,  or  starchy  reserve 
material,  which  serves  as  the  source  of  food  for  the  embryo 
in  the  first  stages  of  growth.  The  embryo  is  composed  of  a 
vegetative  portion,  or  that  part  containing  in  minute  form 
the  leaves  and  roots  of  the  new  plant,  and  the  scutellum, 
which  during  germination  brings  the  starch  or  flour  of  the 
endosperm  into  solution  and  transfers  it  to  the  growing  parts. 

The  first  step  in  germination  is  the  absorption  of  water,  of 
which  the  wheat  kernel  takes  up  from  five  to  six  times  its  own 
weight.  The  outer  layers  of  the  kernel  are  ruptured  and  the 
vegetative  portion  of  the  embryo  begins  to  develop  its  minute 
leaves  and  roots  by  means  of  the  food  derived  from  the  endo- 
sperm, until  finally  parts  of  the  young  plant  appear  above 
the  ground  and  become  green,  thus  showing  that  chlorophyll 
or  leaf -green  has  been  formed.  The  chlorophyll  is  a  sub- 
stance playing  an  important  part  in  the  formation  of  new 
organic  matter  in  the  plant.  At  this  stage  the  roots  begin  to 
take  up  inorganic  matter  held  in  solution  in  the  soil  water 
which  they  absorb,  and  under  the  action  of  air  and  light  the 
young  plant  changes  this  inorganic  matter  into  the  organic 
matter  of  plant  tissue.  All  the  nutritive  material  in  the  en-  . 
dosperm  has  now  been  consumed.  The  process  of  germina- 
tion is  completed  and  the  plant  is  self-supporting. 

THE  ROOTS. 

The  germinating  kernel  of  wheat  produces  a  whorl  of  sev- 
eral small  temporary  roots,  which  are  followed  by  a  set  of 
permanent  roots  thrown  out  from  the  crown,  a  joint  or  group 


view.  Of  joints  in  the  young  stem  usually  about  an  inch  below  the 
surface  of  the  sell.  The  depth  of  the  crown  depends  mainly 
on  the  depth  of  planting.  Roots  may  start  from  any  joint 
or  node  under  or  at  the  surface  of  the  ground.  In  the  early 
stages  of  the  plant  the  development  of  the  roots  is  much 
greater  than  the  growth  of  the  leaves,  the  roots  of  many 
plants  having  obtained  a  length  of  20  inches  when  the  portion 
of  the  plants  above  the  ground  is  not  over  5  inches  in  height. 
The  permanent  root  system  is  fibrous  rnd  branching,  the 
branches  occurring  mainly  in  the  upper  2  feet  of  soil.  Wheat 
commonly  is  considered  a  short-rooted  plant,  but  its  roots 
extend  from  4  to  5  feet  into  the  ground  and  go  much  deeper 
than  those  of  the  ordinary  hay  grasses.  A  cop  ous  and  con- 
tinued moisture  supply  in  the  soi'  tends  to  produce  shallow- 
rooted  plants,  while  smaller  and  barely  sufficient  supplies 
of  soil  water  induce  deeper  rooting.  The  crop  does  not 
thrive  where  conditions  of  the  subsoil,  such  as  a  hardpan  too 
near  the  surface,  interfere  with  the  development  of  the  root 
system.  If  the  seeding  is  shallow  the  temporary  and  the  per- 
manent roots  form  practically  a  single  tuft,  but  if  the  seeding  is 
deep  many  of  the  permanent  roots  or  those  growing  from  the 
crown  are  from  one-half  to  2  or  3  inches  above  the  temporary 
whorl.  As  soon  as  the  permanent  roots  have  become  well 
established,  the  temporary  roots  and  the  seed  kernel  are  no 
longer  of  any  benefit  to  the  growing  plant. 

THE   STEMS. 

The  structure  of  the  stems  or  culms  varies  with  the  kind  of 
wheat.  In  some  types  the  stems  are  thin-walled  and  hollow 
and  in  others  either  thick-walled  or  pithy.  In  all  types  the 
stems  are  jointed,  the  joints  being  known  as  the  nodes  and  the 
parts  between  the  joints  as  the  internodes.  The  first  stem,  or 
the  one  growing  up  directly  from  the  seed,  does  not  always 
reach  complete  development,  but  a  number  of  other  stems  are 
thrown  up  from  the  crown  and  grow  up  to  maturity.  This 
action  of  the  plant,  known  as  tillering  or  stooling,  varies  with 
the  variety  and  the  season.  At  full  growth  well-developed 
wheat  plants  are  from  3  to  5  feet  high,  with  about  five  to  six 
internodes  in  the  erect  portion  of  the  stem. 

THE  LEAVES. 

The  leaves  consist  of  the  sheath,  the  blade,  the  ligule,  and 
the  auricle.  The  sheath  starts  from  the  nodes  or  joints  and 
clasps  the  stem.  The  opening  of  the  sheath  is  on  the  opposite 
side  from  the  blade,  which  is  the  part  extending  outward  from 
the  stem  and  which  varies  in  size,  shape,  texture,  and  vena- 


tion.  The  ligule  is  a  thin,  transparent  tissue,  clasping  the  View- 
stem  where  the  blade  and  the  sheath  join,  and  the  aiiricle  is  a 
fine,  hairy  projection  located  at  the  base  of  the  blade.  The 
first  leaves,  which  come  from  the  crown,  are  set  close  together, 
being  produced  from  the  nodes  before  the  internodes  have 
lengthened.  As  the  stem  or  stems  grow  up  the  leaves  become 
larger  and  are  distributed  at  intervals,  marking  the  length  of 
the  internodes.  6 

THE   HEAD   OR   SPIKE. 

The  head  of  wheat  consists  of  the  rachis,  which  is  a  notched 
extension  of  the  stem,  and  the  spikelets  arranged  upon  it.  The  7 

notches  or  angles  correspond  to  the  nodes  and  the  short  sec- 
tions separating  the  notches  to  the  internodes.  When  the  8 
internodes  of  the  rachis  are  short  the  heads  are  compact  or 
crowded,  and  when  they  are  long  the  heads  are  said  to  be  open. 
The  spikelets  are  the  flower  clusters,  which  ultimately  produce 
the  grain.  Their  number  ranges  from  8  to  10  on  each  side  9 

of  the  rachis  in  some  varieties,  and  from  10  to  16  in  others. 
Each  spikelet,  as  a  rule,  has  five  flowers,  but  the  upper  or  odd 
one  is  rarely  fertile. 

THE   FLOWER   OR   BLOSSOM. 

The  flower  or  blossom  consists  of  the  reproductive  organs,  10 
namely,  the  ovary,  the  pistil,  and  the  stamens.  The  ovary  is 
the  rudimentary  grain  of  wheat  and  with  the  pistil  constitutes 
the  female  portion  of  the  blossom,  while  the  stamens  represent 
the  male  element.  The  pistil  branches  into  two  feathery 
styles  and  is  borne  on  the  ovary,  while  the  stamens,  of  which 
there  are  three,  have  their  filaments  inserted  around  the  base 
of  the  ovary  and  extend  around  and  above  it  so  that  the 
anthers  are  placed  around  the  pistil. 

THE   GRAIN. 

The  kernel  of  wheat  is  the  fruit  of  the  plant.  Its  outer 
covering  is  made  up  of  two  layers,  the  outer  the  epiderm  or 
pericarp,  and  the  inner  the  endocarp.  Beneath  these  layers  is 
the  testa  or  seed  covering,  and  all  three  of  these  coverings 
go  to  make  up  the  bran  in  milling  and  constitute  about  5  per 
cent  of  the  entire  grain.  Immediately  under  the  testa,  or 
seed  covering,  is  a  layer  of  cells  rich  in  gluten,  which,  in  mill- 
ing, is  partly  removed  with  the  bran  and  contributes  largely 
to  the  feeding  value  of  this  product.  The  interior  portion 
of  the  grain  surrounded  by  the  gluten  cells,  called  the  endo- 
sperm, is  composed  mostly  of  starch  but  contains  also  some 
proteid  substances.  The  endosperm,  which  constitutes  about 
75  per  cent  of  the  kernel,  is  the  source  of  flour.  The  germ. 


view.   which  is  located  on  the  opposite  side  of  the  furrow  or  crease 
and  at  the  end  opposite  to  the  brush  or  hairy  tip,  forms  only  a 

11  small  part  of  the  kernel.     The  grain  varies  in  size  and  shape 

12  with  the  type  and  the  variety. 

COMPOSITION. 

Variety,  climate,  and  soil  are  the  principal  factors  which 
determine  the  composition  of  the  wheat  plant.  Normally  the 
grain  of  wheat  contains  about  10  per  cent  of  water,  2  per  cent 
of  ash,  12  per  cent  of  protein,  2  per  cent  of  fiber,  72  per  cent  of 
nitrogen-free  extract,  and  2  per  cent  of  fat.  The  gluten  is 
made  up  from  the  protein  and  the  starch  content  is  included 
under  nitrogen-free  extract.  The  gluten  is  a  mixture  of  two 
proteids,  gliadin  and  glutenin,  and  its  quantity  and  quality 
determine  the  value  of  the  grain  for  baking  purposes.  The 
quality  of  the  gluten  is  governed  to  some  extent  by  the  pro- 
portion of  gliadin  and  glutenin — a  gluten  consisting  approxi- 
mately of  one-fourth  glutenin  and  three-fourths  gliadin  being 
considered  most  satisfactory.  The  starch  is  located  almost 
wholly  in  the  endosperm,  which  constitutes  about  75  per  cent 
of  the  entire  kernel,  and  nearly  all  of  which  is  made  into  flour  in 
the  process  of  milling.  The  nitrogen-free  extract  is  largely 
made  up  of  starch,  the  amount  of  which  varies  from  60  to  70 
per  cent. 

Ordinarily  the  straw,  including  the  chaff,  constitutes  from 
50  to  65  per  cent  and  the  grain  from  35  to  50  per  cent  of  the 
wheat  plant.  The  straw  contains  normally  from  10  to  15  per 
cent  of  moisture,  and  in  addition  approximately  4  per  cent  of 
ash,  3.5  per  cent  of  protein,  40  per  cent  of  crude  fiber  or  cel- 
lulose, 45  per  cent  of  nitrogen-free  extract,  and  1.5  per  cent 
of  fat.  The  chaff  contains  more  phosphoric  acid  and  also  a 
little  more  protein  but  less  crude  fiber  than  the  straw. 

TYPES   AND   VARIETIES. 

The  varieties  of  wheat  are  divided  into  groups  according  to 

13  botanical  characters,  and  in  some  cases  these  again  are  divided 

14  according    to    characteristics    due    to    environment    or   geo- 
graphical  distribution. 

Owing  to  the  wide  geographical  distribution  of  the  plant, 
the  varieties  of  wheat  are  more  numerous  than  those  of  any 
other  cereal  except  rice.  In  addition  to  the  botanical  classi- 
fication, a  number  of  other  classifications  are  in  use,  as,  for 
instance,  the  market  classification  embracing  the  different 
types  recognized  by  the  grain  markets,  such  as  soft  winter, 
hard  winter,  hard  spring,  and  white  wheats;  the  classification 
based  on  external  characters,  which  groups  the  varieties  into 


spring  and  winter  wheats,  bearded  or  awned  and  beardless  or   Vlew 
awnless  varieties,  white  and  red  wheats,  hard  and  soft  sorts, 
early  and  late  varieties,  etc.     The  soft  wheats  also  are  called 
starchy  wheats  and  the  hard  wheats  glutinous  wheats.     The 
common  wheats  include  all  varieties  excepting  those  used         15 
in  the  preparation  of  macaroni,  spaghetti,  and  other  pastes. 

Varieties  of  wheat  differ  greatly  in  productiveness,  hardiness, 
drought  resistance,  resistance  to  lodging,  quality  of  grain,  and 
in  other  characters.  There  are  always  best  varieties  for  cer- 
tain soils  and  regions  but  no  varieties  that  succeed  best  under 
all  conditions.  It  costs  no  more  to  grow  a  good  variety  than 
a  .poor  one,  and  it  is  therefore  to  the  farmer's  interest  to  ob- 
tain the  best  sort  for  his  locality.  All  varieties  grown  in  the 
vicinity  should  be  observed  and  the  best  one  selected.  Varie- 
tal strains  in  their  own  locality  are  likely  to  give  better  results 
than  strains  of  the  same  variety  brought  from  a  distance  be- 
cause there  is  little  or  no  change  in  environment. 

IMPROVEMENT   OF   VARIETIES. 

Wheat  varieties  are  improved  mainly  by  selection  and  cross- 
ing. Improvement  by  selection  comprises  the  selection  of  seed 
and  the  selection  of  individual  plants.  Varieties  may  be  im- 
proved by  selection  or  by  crossing  and  selection  together. 
Most  varieties  now  grown  are  the  result  of  simple  selection, 
and  this  kind  of  work  is  often  very  profitable  and  replete  with 
satisfaction.  Dawson  Golden  Chaff,  for  instance,  had  its 
origin  in  a  single  stool  of  White  Clawson  wheat  which  had  been 
the  only  one  to  survive  winter  in  a  bare  and  exposed  position. 
This  variety  has  given  excellent  results  in  New  York,  Michigan, 
and  Canada,  and  is  a  standard  sort  in  many  localities.  This 
instance  is  one  of  the  many  showing  the  importance  of  select- 
ing individual  plants. 

The  crossing  of  varieties  is  effected  by  means  of  artificial         16 
cross-fertilization.     The  stamens  must  be  removed  from  the         17 
the  blossom  before  the  pollen  sacks  are  mature  enough  to  break 
and  to  pollinate  the  pistil.     After  this  is  done  the  pistil  must 
be  protected  from  the  pollen  of  other  flowers  borne  either  in 
the  same  or  in  other  heads.     Usually  all  the  flowers  not  de- 
sired for  crossing  are  removed  and  the  entire  head  is  then 
wrapped  in  tissue  paper  and  the  pollen  of  the  variety  chosen         18 
as  the  male  parent  applied  to  the  stigmas  when  these  are  in 
proper  condition.     As  soon  as  the  application  of  pollen  is  made         19 
the  heads  are  carefully  covered  to  keep  other  pollen  from  en- 
tering and  possibly  fertilizing  the  blossom.     The  resulting  seed         20 
is  planted  and  the  crops  for  several  years  are  subjected  to 
rigid  selection  to  fix  the  variety.  21 


8 

View.  GEOGRAPHICAL   DISTRIBUTION. 

Although  wheat  *is  grown  under  a  very  wide  range  of 
climatic  conditions,  the  bulk  of  the  world's  crop  is  produced 
in  the  temperate  zones.  The  quality  of  wheat  in  the  different 

22  parts  of  the  world  varies  with  the  climate,  and  even  in  this 
country  wheat  differs  in  quality  in  the  various  wheat-producing 
sections. 

CHOICE  AND   PREPARATION   OF  THE   SOIL. 

Light  fertile  clay  and  medium  fertile  loam  soils  of  good 
depth  and  well  drained  are  best  adapted  to  wheat  culture. 
Heavy  clays  are  too  compact  and  are  inclined  to  bake,  and 
highly  fertile  loams  tend  to  lodge  the  crop.  Light  clay  soils 
having  the  proper  degree  of  compactness  and  being  suf- 
ficiently retentive  of  moisture  are  better  adapted  to  winter 
wheat  than  are  the  loams.  The  clay  soils  are  usually  up- 
lands, and  the  loam  soils  are  either  lowlands  or  prairies. 
The  alluvial  soils  of  river  bottoms,  if  not  too  rich,  usually  make 
good  wheat  lands,  because  they  are  deep  and  fertile  and 
generally  made  up  of  clay,  sand,  and  humus  in  proportions, 
making  them  friable  and  porous  and  giving  good  drainage. 
The  loams  are  primarily  corn  lands,  but  in  connection  with 
corn  culture  are  well  suited  to  spring  wheat.  Very  light,  loose 
or  sandy  soils  and  wet,  peaty,  sour  lands  are  unfit  for  the 
wheat  crop. 

Drainage  is  necessary  to  a  profitable  development  of  the 
wheat  plant,  and  a  permeable  subsoil  is  especially  important 
during  the  most  active  stages  of  its  growth  and  to  winter 
wheat  also  in  the  late  fall  and  winter.  Where  the  subsoil  is 
not  sufficiently  permeable,  proper  drainage  should  be  provided 
by  putting  down  tile,  as  this  is  generally  the  most  satisfactory 
and  economical  method  of  draining. 

The  character  of  the  soil  influences  the  yield  to  a  greater 
extent  than  it  affects  the  quality,  which  is  largely  controlled 
by  climatic  conditions.  That  the  two  factors  are  closely 
connected  is  shown  by  the  durum  wheats,  which  require  rich 
humus  soils  and  hot  and  dry  seasons.  Soils  high  in  organic 
matter  tend  to  increase  the  protein  content  and  the  hardness 
of  the  grain. 

Land  for  wheat  should  be  plowed  several  weeks  before  sow- 
ing time  in  order  to  bring  about  the  most  favorable  conditions 
for  a  rapid  and  regular  germination  of  the  seed.  After  plow- 

23  ing,  the  soil  should  be  allowed  to  settle  and  the  moisture 
content  at  the  surface  to  increase  before  the  seed  is  sown. 
By  harrowing  or  disking  the  land  at  intervals  from  the  time 

24  it  is  plowed  until  it  is  seeded  down  weeds  are  destroyed  and 


soil  moisture  is  conserved,  while  the  seed  bed  is  made  smooth,    view- 
fine,  and  ev«n.     Numerous  small  clods  on  the  surface,  how- 
ever, may  be  of  value  in  holding  the  snow  on  winter  wheat 
fields  and  in  preventing  or  reducing  soil  washing. 

Deep  plowing  is  not  of  general  value  and  often  seems  to 
affect  the  yield  of  straw  more  than  the  yield  of  grain.  Plow- 
ing from  4  to  6  inches  deep  is  adequate,  especially  if  the  land 
is  in  good  tilth.  Subsoiling  is  expensive  and  frequently 
unprofitable  in  wheat  culture.  On  friable  and  mellow  soils 
plowing  is  unneccessary  if  the  land  was  well  cultivated  the 
year  before  in  connection  with  growing  corn  or  other  hoed  crops. 
On  such  land  a  seed  bed  can  be  prepared  by  disking  or  cultiv-  25 
ating  and  harrowing. 

If  the  plowing  is  done  when  it  is  too  wet  the  soil  is  likely  to 
harden  or  bake,  and  if  done  when  too  dry  the  ground  remains 
rough  and  lumpy.  It  should  be  remembered  that  in  growing 
wheat  and  other  similar  plants  the  tillage  of  the  crop,  as  it 
were,  is  performed  before  and  at  the  time  the  seed  is  sown.  In 
the  semiarid  regions  the  success  of  the  crop  depends  often 
entirely  upon  the  careful  and  thorough  cultural  treatment 

given  the  land. 

MANURING. 

The  fertility  of  wheat  land  may  be  maintained  and  im- 
proved by  the  use  of  barnyard  manure,  commercial  fertilizers, 
and  green  manures,  and  by  proper  crop  rotations  and  fallowing. 
No  generally  applicable  rule  for  fertilizing  wheat  lands  can  be 
laid  down,  but  certain  underlying  principles  are  operative 
everywhere.  Wheat  straw  contains  approximately  0.6  per 
cent  of  nitrogen,  0.2  per  cent  of  phosphoric  acid,  and  0.6  per 
cent  of  potash,  and  the  grain  about  2  per  cent  of  nitrogen, 
0.85  per  cent  of  phosphoric  acid,  and  0.55  per  cent  of  potash. 
This  means  that  a  ton  of  straw  removes  from  the  soil  12 
pounds  of  nitrogen,  4  pounds  of  phosphoric  acid,  and  12 
pounds  of  potash,  and  a  ton  of  grain,  or  33  J  bushels,  40  pounds 
of  nitrogen,  17  pounds  of  phosphoric  acid,  and  11  pounds  of 
potash.  These  figures  call  attention  to  the  importance  of 
returning  at  least  the  straw  in  the  form  of  manure  to  the  land 
and  also  point  to  the  fact  that  continued  wheat  growing  for 
the  market  must  deplete  the  fertility  of  the  soil. 

Barnyard  manure  is  preferably  applied  to  the  corn  crop 
before  wheat.  When  manure  is  directly  applied  to  winter 
wheat  it  should  be  spread  and  plowed  under  immediately 
after  the  preceding  crop  is  removed,  in  order  that  it  may  be- 
come well  embedded  in  the  soil  before  the  seed  is  sown.  In 
such  cases  the  use  of  10  tons  per  acre  is  sufficient  and  generally 
27849°— 18 2 


10 

view,  ^u  gjve  better  results  than  double  that  quantity.  When 
barnyard  manure  is  used  as  a  top-dressing  for  wheat  it  should 
be  well  rotted  and  finely  divided,  and  preferably  spread  with 
a  wide-tired  manure  spreader.  On  most  loams  and  alluvial 
soils  on  which  wheat  is  grown  in  rotation  the  use  of  barnyard 
manure,  especially  its  direct  use,  is  unnecessary,  but  on  light 
clay  soils  it  often  proves  profitable. 

The  application  of  large  quantities  of  available  nitrogen, 
either  in  commercial  fertilizers  or  barnyard  manure,  usually 
results  in  a  heavy  growth  of  straw  and  a  consequent  tendency 
to  lodge.  A  complete  fertilizer,  or  one  containing  nitrogen, 
phosphoric  acid,  and  potash,  is  generally  to  be  recommended, 
and  while  no  rule  applicable  to  all  cases  can  be  laid  down,  the 
use  of  300  to  500  pounds  of  a  fertilizer  mixture  furnishing  in 
plant  food  3.3  per  cent  of  nitrogen,  12  per  cent  of  available 
phosphoric  acid,  and  4  per  cent  of  potash  is  very  common. 
Ordinarily  on  poor  soils  the  application  of  nitrogen  and  potash 
may  be  relatively  high,  but  on  soils  in  a  fairly  good  state  of 
fertility  the  quantity  of  these  elements  may  be  reduced. 
Commercial  fertilizers  are  more  profitable  as  a  rule  on  clay 
soils  than  on  the  richer  loams,  and  throughout  the  western 
wheat  area  of  the  country  they  are  little  used.  Appli cations 
26  of  25  to  40  bushels  of  lime  per  acre  are  often  very  beneficial, 
especially  on  soils  treated  with  sulphate  and  chlorid  of  am- 
monia for  a  series  of  years.  Top-dressings  with  nitrate  of  soda 
are  sometimes  given  after  the  crop  has  made  some  growth, 
but  if  the  plants  are  in  a  vigorous  condition  in  the  spring  no 
top-dressing  is  necessary. 

Green  manuring  with  leguminous  crops  is  very  desirable, 
but  when  a  heavy  green  crop  is  plowed  under  it  is  best  to 
follow  it  with  a  hoed  crop  before  putting  the  land  into  wheat. 
Benefit  is  derived  also  when  leguminous  plants  are  grown  before 
wheat  and  other  crops  and  only  the  stubble  is  plowed  under. 

Summer  fallowing,  which  is  seldom  followed  in  humid  sec- 
tions, is  practiced  very  extensively  in  some  of  the  wheat 
regions  on  the  Pacific  coast  and  in  those  Western  States  where 
dry-farming  methods  are  required.  To  mature  profitable 
crops  the  land  in  some  of  these  sections  requires  the  rainfall 
of  two  seasons,  and  hence  wheat  generally  is  grown  on  land 
that  has  had  a  season  of  rest  and  has  stored  up  sufficient 
moisture  to  supply  the  demands  of  the  crop.  Cultivation  of  the 
summer  fallow  is  practiced  to  conserve  the  soil  moisture  and  to 
increase  the  store  of  available  plant  food.  On  lands  that  receive 
adequate  rainfall  summer  fallow  can  not  be  as  profitable  as 
the  culture  of  some  leguminous  crop,  which  not  only  adds 


11 

nitrogen  and  humus  to  the  soil,  but  also  prevents,  or  at  least   View- 
largely  reduces,  leaching. 

SEED   AND   SEEDING. 

Seed  wheat,  besides  being  all  of  one  variety,  also  should  be 
heavy,  plump,  and  free  from  dirt,  weed  seeds,  and  injured  or 
immature  kernels.  A  pure  variety  is  always  to  be  preferred 
to  a  mixture  of  varieties,  however  slight  this  may  be.  Heavy 
seed  promotes  stooling  and  the  production  of  strong  plants, 
and  increases  yield  and  quality  of  grain  as  well  as  yield  of  straw. 
In  most  cases  where  heavy  seed  has  been  compared  with  small  27 
or  light  seed,  the  results  have  been  in  favor  of  the  heavy  seed. 
Some  injured  or  immature  seed  may  sprout  successfully,  but, 
due  to  insufficient  food  supply  or  imperfectly  developed  germs,  28 
the  plants  soon  die.  Wheat  that  has  become  heated  or  moldy 
in  storage  may  not  grow  at  all  or  else  have  only  a  low  percentage 
of  germination.  It  is  advisable,  therefore,  to  make  a  germina- 
tion test  to  determine  the  vitality  and  the  viability  of  the  seed. 
This  may  be  done  by  placing  the  kernels  between  folds  of  cloth 
or  blotting  paper,  one  end  of  which  is  placed  in  water  so  that  the 
moisture  is  supplied  through  capillarity,  and  keeping  this  im- 
provised germinator  at  the  ordinary  room  temperature,  never 
allowing  it  to  fall  below  50°  F.  Wheat  cleaned  with  a  fanning 
mill  is  used  for  seed  generally,  but  a  much  better  way,  although 
little  practiced,  is  to  select  each  year  from  the  best  plants  grown 
on  a  special  seed  plat  the  best  seeds  for  use  in  planting  the  seed 
plat  for  the  foUowing  season,  and  use  the  rest  of  the  seed-plat 
crop  for  sowing  the  general  field. 

The  time  of  sowing  is  determined  by  the  season,  the  variety 
of  the  wheat,  the  nature  and  fertility  of  the  soil,  the  altitude 
and  latitude  of  the  locality,  and  sometimes  by  the  prevalence  of 
insect  enemies,  especially  the  Hessian  fly,  and  existing  weather 
conditions.  In  the  North  winter  wheat  is  sown  earlier  and 
spring  wheat  later  than  in  the  South.  In  the  southern  winter- 
wheat  regions  the  seed  is  preferably  sown  la£e  in  September 
or  early  in  October;  in  Ohio,  Indiana,  Illinois,  Iowa,  and 
Nebraska,  from  September  10  to  20;  and  in  some  of  the  extreme 
northern  winter-wheat  regions,  as  early  as  the  last  week  in 
August  or  the  first  week  in  September.  Spring  wheat  gen- 
erally is  sown  as  soon  in  the  spring  as  the  seed  bed  can  be 
prepared  properly. 

The  germination,  stooling  process,  and  underground  growth 
of  winter  wheat  takes  place  when  the  soil  temperature  is  from 
42°  to  50°  F.  When  this  temperature  prevails  for  a  sufficient 
length  of  time  during  winter  the  wheat  stools  and  produces 


12 

view,  underground  growth,  and  when  the  continued  warmer  weather 
of  spring  arrives  the  different  stems  shoot  upward  and  develop 
their  leaves  and  lengthen  their  internodes  rapidly. 

The  depth  of  sowing  depends  mainly  upon  the  kind  of  soil 
and  its  physical  condition.  The  object  always  should  be  the 
provision  of  the  best  moisture  conditions  for  the  seed.  In 
moist  soils  or  soils  of  a  hard  texture  shallow  seeding  is  prac- 
ticed, but  in  loose  or  dry  soils  deeper  seeding  is  necessary. 
The  usual  depth  of  sowing  wheat  is  from  1  to  2  inches.  When 
the  seed  kernel  lies  deep  the  portion  of  the  young  stem  con- 
necting it  with  the  crown  is  necessarily  longer  than  when  it 
lies  nearer  the  surface  of  the  ground,  as  in  the  case  of  shallow 
seeding.  Heaving  of  the  surface  soil,  due  to  frost  or  other 
cause,  may  break  the  young  stem,  separating  the  crown  and 
other  parts  of  the  plant  from  the  primary  root  system.  This 
condition  is  detrimental  to  the  plant  it  if  occurs  before  the 
permanent  roots  are  large  enough  to  take  up  the  necessary 
food  and  moisture. 

The  quantity  of  seed  used  per  acre  depends  upon  the  kind 
of  soil  and  its  physical  condition,  the  climate  and  the  season, 
the  time  and  method  of  sowing,  the  variety,  and  the  size  and 
quality  of  the  seed.  As  a  general  rule  wheat  is  sown  thicker 
on  poor  soils,  stiff  and  cold  clay  lands,  and  rough  and  cloddy 
seed  beds  than  on  fertile  soils,  friable  loams,  and  fields  well 
worked  and  smoothed  before  seeding.  Late  sowing  and 
broadcasting  also  require  more  seed  than  early  sowing  and 
drilling.  A  large-grained  variety  requires  a  greater  quantity 
of  seed  than  a  fine-grained  sort,  and  a  variety  with  limited 
stooling  capacity  more  than  a  heavy  stooling  variety.  The 
proper  quantity  of  seed  per  acre  varies  from  3  to  8  pecks. 

Two  common  methods  of  sowing  wheat  are  drilling  and 
broadcasting.  Different  kinds  of  machines  are  used  for  both 
operations,  but  broadcasting  is  done  also  by  hand.  Drilling 
is  done  with  common  drills,  press  drills,  shoe-and-chain  drills, 
disk  drills,  etc.*  Each  method  has  its  advantages  under  cer- 
tain conditions.  The  greater  portion  of  the  wheat  crop  is 
29  drilled.  Winter  wheat  sometimes  is  rolled  in  the  early  spring 
to  counteract  in  part  the  results  of  winter  heaving  of  the  soil. 
Harrowing  wheat  in  the  spring  after  the  crop  has  made  some 
growth  has  given  favorable  results  hi  some  instances,  but  it  is 
not  practiced  generally.  Late  rolling  and  late  harrowing  are 

often  injurious. 

CROP  ROTATIONS. 

The  place  of  wheat  in  the  crop  rotation  is  governed  largely 
by  the  cleanness  of  the  soil,  the  adaptability  of  wheat  as  a 


13 

nurse  crop  for  clover  and  grass,  the  possibility  of  either  fall   View 
or  spring  sowing,   the  comparatively  early  ripening  of  the 
crop,  the  fertility  of  the  soil,  and  other  conditions. 

Hoed  crops  and  summer  fallow,  especially  if  cultivated, 
tend  to  leave  a  greater  quantity  of  water  in  the  soil  than 
growing  broadcasted  and  uncultivated  crops,  such  as  the 
small  grains,  In  a  dry  season,  for  this  reason,  wheat  after 
corn  or  cultivated  summer  fallow  is  likely  to  give  a  much 
better  yield  than  if  grown  after  wheat  or  oats.  On  some  new 
soils  wheat  sometimes  is  grown  for  several  years  in  succession 
on  the  same  land,  but  continuous  cropping  experiments  have 
shown  that  after  a  series  of  years  the  yields  begin  to  decline, 
and  rotation  experiments  have  indicated  clearly  that  better 
yields  are  obtained  from  soils  under  rotation  than  those 
growing  wheat  year  after  year. 

IRRIGATION   AND   RAINFALL. 

Successful  wheat  culture  does  not  depend  so  much  upon 
the  total  annual  rainfall  as  upon  the  amount  of  moisture  the 
soil  furnishes  the  crop  during  the  growing  period.  The  total 
rainfall  in  some  of  the  wheat-growing  localities  of  the  West  and 
Northwest  ranges  annually  from  12  to  18  inches  and  yet 
good  crops  are  produced  without  irrigation;  but  in  other  sec- 
tions the  same  amount  of  rainfall  is  insufficient  for  a  profit- 
able yield.  Again,  in  many  humid  regions  where  the  yearly 
precipitation  is  as  much  as  40  inches,  most  of  the  water  runs 
off  in  the  drainage,  less  than  half  of  the  total  precipitation 
being  available  to  the  growing  plants.  The  question,  therefore, 
is  not  alone  how  much  rainfall  there  is,  but  how  much  of  it  is 
retained  by  the  soil  for  the  use  of  the  crop.  The  relation  of 
rainfall  to  wheat  culture  is  largely  a  question  of  soil  condi- 
tions. It  is  a  significant  fact  that  a  very  large  proportion  of 
the  wheat  of  the  world,  as  well  as  a  superior  quality  of  grain, 
is  produced  in  rather  dry  regions  or  on  lands  subject  to  ex- 
tremes of  temperature  and  drought. 

Wherever  or  whenever  the  rainfall  is  deficient,  irrigation 
generally  insures  a  crop  and  secures  larger  yields  and  better 
grain.     It   must   be   practiced    judiciously,    however,    to   be 
successful.     Furrow    irrigation   is   considered    best   in   some        30 
sections  and  flooding  in  others.     Irrigation  sometimes  has  a 
marked  influence  on  the  composition  of  the  grain.     At  the 
time  the  kernel  is  filling  out,  the  soil  should  be  properly  sup- 
plied with  moisture  to  promote  the  production  of  full  and         31 
plump  grain.     Too  much  water  at  this  period  has  a  tendency         32 
to  yellow  the  crop,  retard  its  maturity,  and  lower  the  yield. 


14 

view.  paj]  irrigation  of  winter  wheat  has  been  found  beneficial 
when  the  soil  lacked  moisture  for  the  production  of  the  neces- 
sary fall  growth.  One  or  two  irrigations  are  sufficient  for 
winter  wheat  in  the  spring.  When  the  water  is  applied  in 
the  evening,  about  sunset,  the  evaporation  from  the  surface 
of  the  soil  is  much  less  than  when  it  is  applied  during  the  day, 
and  it  also  frequently  results  in  a  higher  yield  of  straw  and 
grain. 

WHEAT   GROWING   IN  THE   SEMIARID   REGIONS. 

Wheat  is  the  principal  crop  of  our  semiarid  regions.  Its 
successful  production  there  depends  largely  upon  the  use  of 
varieties  adapted  to  the  conditions  and  upon  cultural  methods 
based  largely  on  soil  moisture  conservation.  Hard  spring 
wheats  and  winter  wheats  are  grown.  The  hard  spring  wheats 
grown  in  the  northern  part  of  the  Great  Plains  area  include 
the  durum  wheats  and  varieties  of  the  common  wheats,  those  of 
the  Bluestem  and  Fife  groups  being  prominent.  The  winter 
wheats  produced  over  the  larger  part  of  our  semiarid  area  are 
represented  mainly  by  hard  winter  wheats,  as  Crimean, 
Kharkov,  Turkey,  and  others  cultivated  largely  in  the  Great 
Plains  area;  the  semihard  winter  wheats  grown  in  the  Great 
Basin  region;  and  the  soft  winter  wheats  extensively  produced 
in  the  Pacific  Coast  States. 

Cultural  operations  involve  mainly  the  preparation  of  the 
seed  bed  with  a  view  to  furnishing  adequate  moisture  and  in 
the  case  of  winter  wheat  to  provide  also  protection  against 
unfavorable  winter  weather.  The  land  for  spring  wheat 
should  be  plowed  the  preceding  summer  or  fall  and  afterward 
given  surface  cultivation  at  intervals  until  seeding  time.  For 
winter  wheat  early  and  deep  fall  plowing  is  desirable  in  some 
sections,  while  in  others  late  and  shallow  plowing  is  the  more 
profitable.  Much  depends  on  the  season  and  the  soil,  as 
seasonal  variations  give  unexpected  results  and  some  soils  are 
little  responsive  to  cultural  methods.  Furrowing  with  a  lister 
after  harvest  and  leveling  the  ridges  preparatory  to  seeding 
is  practiced  sometimes  in  preference  to  plowing  and  with 
satisfactory  results.  Subsoiling  in  general  has  not  met  expec- 
tations in  overcoming  drought,  increasing  yields,  or  returning 
profits.  Disking  corn  ground  as  a  soil  preparation  instead  of 
plowing  has  given  good  yields  as  a  rule  and,  in  addition,  has 
reduced  the  labor  cost.  Summer  tillage,  together  with  crop- 
ping in  alternate  years — a  method  in  very  general  use — gives 
comparatively  high  average  yields,  but  on  account  of  its  high 
labor  cost  and  the  production  of  a  crop  only  every  other  year 


15 

does  not  always  net  the  largest  returns.  Compared  with  spring  view- 
wheat,  winter  wheat  is  the  more  profitable  crop  on  tilled  sum- 
mer fallow.  In  sections  where  winterkilling  is  common,  seed- 
ing in  standing  cornstalks  or  in  small  grain  stubble  without 
preparation  is  often  resorted  to  as  a  means  of  winter  pro- 
tection. 

Winter  wheat  is  commonly  sown  at  the  rate  of  3  pecks  and 
spring  wheat  of  about  4  or  5  pecks  per  acre.  AH  seed  should 

be  drilled. 

HARVESTING. 

The  time  of  harvesting  wheat  is  controlled  mostly  by  the 
latitude  and  the  seasons.  The  world  harvests  wheat  in  every 
month  of  the  year.  In  general  practice  wheat  is  cut  when 
the  heads  have  turned  yeUow  but  while  the  stems  are  still 
slightly  green  and  the  kernel  in  the  hard-dough  stage.  In  the 
greater  portion  of  the  wheat-producing  area  of  this  country 
harvesting  must  be  done  in  from  8  to  10  days  to  prevent 
losses  from  shattering.  Varieties  grown  in  some  sections, 
such  as  the  club  wheats  in  the  Pacific  Coast  States,  do  not 
shatter  so  readily  as  the  varieties  commonly  grown  in  the 
Mississippi  Valley  and  Eastern  States.  The  state  of  ripening 
influences  the  composition  of  the  plant.  The  dry  matter 
in  the  entire  plant  increases  up  to  maturity  and  the  kernel 
increases  in  starch  content  as  it  develops. 

In  most  countries  harvesting  now  is  done  largely  by  means        33 
of  the  self-binder,  although  the  header,  self-made  reaper,  and        34 
combined  harvester  and  thrasher  also  are  used.     In  sections        35 
where  labor  is  cheap  and  the  machines  costly,  cutting  with  the        36 
cradle  and  binding  by  hand  are  still  practiced.     Immediately 
after  cutting  and  binding,  the  sheaves  are  put  up  into  shocks 
to  protect  them  against  dew,  rain,  and  the  sun,  and  to  facilitate 
curing  and  ripening  in  the  shock.     Round  shocks  usually  con- 
tain from  12  to  16  sheaves,  of  which  2  are  used  as  a  cap  or 
cover.     Long  shocks  are  made  by  placing  12  or  14  sheaves  as 
pairs  in  a  row,  and  are  used  when  the  sheaves  are  wet,  to 
facilitate  rapid  and  thorough  drying. 

The  crop  is  either  kept  in  the  shock  until  thrashed  or  is 
stacked  when  sufficiently  dry  and  thrashed  later  on.  Stacking 
is  a  greater  safeguard  against  injury  to  the  crop  through  bad 
weather.  In  a  properly  built  stack  there  is  a  slant  from  any 
point  in  the  interior  toward  the  outside.  A  few  days  after 
stacking,  a  slight  heating  of  the  grain,  commonly  called  sweat- 
ing, sets  in,  and  this  may  continue  for  one  or  two  weeks.  If 
the  wheat  is  not  allowed  to  sweat  in  the  stack  the  thrashed 
grain  will  sweat  in  the  bin. 


16 

vfew.       Ag  jn  £he  methods  of  harvesting,  so  in  the  methods  of  thrash- 
ing great  changes  have  taken  place.     In  former  times  the  flail 

37  was  used  or  the  grain  was  trodden  out  by  horses  or  oxen,  and 

38  these  methods  are  still  practiced  where  agriculture  is  con- 
ducted on  a  small  scale  or  in  a  primitive  manner.     Generally, 
however,  to-day  thrashing  machines  are  operated  by  horse, 
steam,  gas  engine,  and  electric  power.     A  great  improvement 
in  machines  also  has  been  made,  the  largest  recent  improved 
outfits  under  favorable  conditions  being  capable  of  turning 
out  as  many  as  2,000  bushels  in  one  day.     Formerly  from  500 
to  600  bushels  were  considered  a  good  day's  run. 

STORAGE. 

39  In  storing  wheat  the  object  should  be  to  keep  it  dry  and  to 

40  prevent  insect  depredations.     Stored  wheat  often  changes  in 

41  weight  as  a  result  mainly  of  variations  in  moisture  content.     In 

42  dry  climates  slight  gains  in  weight  occur  during  winter  storage, 
and  wheat  harvested  and  cured  under  arid  conditions  and  then 
transported  to  humid  climates  will  at  times  show  marked  gains 
in  weight  during  transit  and  storage.     In  humid  regions  wheat 
has  a  tendency  to  lose  in  weight  after  thrashing,  but  in  arid 
and  semiarid  climates  this  tendency  is  not  so  apparent. 

THE   USES   OF   WHEAT. 

The  principal  value  of  wheat  lies  in  its  use  for  the  manufac- 
ture of  flour  for  bread  and  pastry.  The  flour  of  durum  wheat, 
generally  richer  in  gluten  than  the  flour  of  common  wheats,  is 
used  for  macaroni,  spaghetti,  and  other  pastes.  The  by- 
products of  the  mill  are  used  for  feedirg  purposes  and  the  chaff 
and  straw  for  feed  and  bedding.  Winter  wheat  also  is  pas- 
tured in  southern  sections,  where  it  makes  a  comparatively 
large  growth  in  the  fall  or  winter,  but  caution  should  be  used 
in  following  this  practice. 

DISEASES   AND   INSECT  ENEMIES. 

43  The  most  common  diseases  of  wheat  are  the  rusts  and  smuts, 

44  and  the  most  common  insect  enemies  the  chinch  bug  and  the 
Hessian  fly.     The  cojnmon  rusts  are  the  orange-leaf  rust  (Pue- 
cinia  rubigo-vera)  and  the  black  rust  (P.  graminis).     The  most 
injurious  smut  is  the  stinking  smut  or  bunt  (Tilletia  fatens] . 

45  The  loose  smut  ( Ustilago  tritici)  is  much  less  injurious  than  the 
stinking  smut.     Injuries  to  the  wheat  crop  from  the  chinch 
bug  and  the  Hessian  fly  are  often  very  extensive.     For  the 
prevention  of  stinking  smut  seed  wheat  is  either  soaked  in  hot 
water  (132°  to  133°  F.)  for  10  to  15  minutes,  immersed  in  a 


17 

solution  of  formaldehyde  in  water  and  the  smut  balls  skimmed  VIew- 
off  (formalin  treatment),  or  dipped  in  a  solution  or  copper  sul- 
phate in  water.  The  loose  smut  can  not  be  prevented  by  dis- 
infecting the  surface  of  the  seed,  but  a  modified  hot-water 
treatment,  consisting  of  soaking  the  seed  for  at  least  4  and  not 
over  6  hours  in  cold  water,  then  draining  it  and  placing  it  for 
10  minutes  in  water  at  129°  F.  (never  above  131°  F.)  may  be 
applied.  This  modified  treatment  is  not  well  adapted  to 
large  quantities  of  seed. 

Chinch  bugs  are  destroyed  by  burning  them  in  their  places 
of  hibernation  and  by  plowing  and  harrowing  them  under 
after  they  have  occupied  decoy  strips.  The  main  factors  in 
the  control  of  the  Hessian  fly  are  good  seed,  a  well-prepared 
and  fertile  soil,  and,  in  the  case  of  winter  wheat,  sowing  after 
most  of  the  fall  brood  has  disappeared.  Spring  wheat,  how- 
ever, should  be  sown  as  early  as  possible. 

Since  the  date  of  safely  sowing  winter  wheat  for  the  escape 
of  the  crop  generally  from  Hessian  fly  varies  greatly  in  the  dif- 
ferent wheat  sections  of  the  United  States  and  even  in  different 
localities  in  a  single  State,  and  also  since  the  proper  date  for 
a  single  locality  differs  from  year  to  year,  the  county  agent 
should  correspond  regarding  this  subject  with  the  entomolo- 
gist at  the  agricultural  college  or  experiment  station  or  with 
the  Bureau  of  Entomology,  United  States  Department  of 
Agriculture,  to  obtain  specific  information  for  his  particular 

county. 

PRODUCTION,   YIELDS,   AND   STATISTICS. 

The  average  yield  of  wheat  for  the  years  1905-1914,  inclu- 
sive, in  different  countries  was  as  follows:  Belgium  36.4, 
United  Kingdom  33.4,  Germany  30.7,  Austria  20.2,  France 
20.1,  Hungary  18.1,  United  States  14.8,  and  Russia  9.8  bushels 
per  acre.  In  1915,  the  United  States  produced  673,947,000 
bushels  of  winter  wheat  on  41,308,000  acres,  the  average  yield 
being  16.3  bushels  per  acre;  and  of  spring  wheat  351,854,000 
bushels  on  19,161,000  acres,  the  average  production  being  18.4 
bushels  per  acre.  This  was  the  largest  wheat  crop  on  record 
and  the  largest  yield  ever  produced  by  any  one  country.  In 
1911,  Denmark  grew  44.6  bushels  per  acre,  Belgium  39.5 
bushels,  the  Netherlands  38.7  bushels,  Ireland  36.8  bushels, 
and  Great  Britain  32.9  bushels.  These  average  yields  indicate 
that  a  large  number  of  growers  raise  40,  50,  and  even  60 
bushels  to  the  acre.  A  comparison  of  the  average  yields  in 
the  United  States  and  these  countries,  together  with  the  soil 
and  climatic  conditions  prevailing  here  and  abroad,  would 


18 

View-  lead  to  the  conclusion  that  the  same  high  yields  can  be  secured 
in  many  sections  of  this  country,  provided  the  same  care  is 
given  to  the  selection  of  the  variety  and  the  seed  and  to  the 
tillage  of  the  soil.  In  this  connection,  however,  the  produc- 
tion per  man  as  well  as  the  production  per  acre  must  be  taken 
into  consideration.  It  is  estimated  that  in  the  United  States 
9.3  acres  of  crops  are  grown  per  capita  of  farm  population,  as 
compared,  for  instance,  with  2.4  acres  in  the  United  Kingdom, 
and  higher  yields  per  acre  in  the  latter  country  may  therefore 
be  expected.  The  problem  before  the  wheat  grower  in  the 
United  States  is  the  economical  increase  in  production,  and 
economic  conditions  must  determine  not  only  its  feasibility 
but  also  whether  larger  returns  are  to  be  obtained  from  each 
acre  or  each  worker,  or  from  both. 


APPENDIX. 


LANTERN   SLIDES. 

No.  of 
view. 

1 .  Cross  sections  of  wheat  grains,  showing  embryo  and  endosperm. 

2.  Wheat  roots. 

3.  Different  types  of  wheat  stems. 

4 .  Stem  of  different  lengths. 

5.  Sheath,  auricle,  and  ligules. 

6.  The  distribution  of  leaves  and  the  length  of  the  internodes. 

7.  The  rachis. 

8.  Crowded  and  open  heads  and  types  of  spikes. 

9.  Spikelets. 

10.  Reproductive  organs  of  wheat. 

11 .  Different  types  of  wheat  grains. 

12.  Grains  of  different  varieties. 

No.  1,  Red  Fife  from  North  Dakota;  No.  2,  Zimmerman  from  Kansas;  No.  3,  Turkey  Red  from 
Kansas;  No.  4,  Fultz  from  Nebraska;  No.  5,  Glyndou  (638)  from  North  Dakota;  No.  6,  Rieti 
from  Italy. 

13.  Grains  of  different  species  of  Triticum. 

No.  13,  Polish  wheat;  No.  14,  Einkorn;  No.  15,  Black  Velvet  emmer;  No.  16,  Red  Winter  Club 
spelt;  No.  17,  Volo:  No.  18,  En  grain  double. 

14.  Heads  and  grains  of  durum  wheat. 

15.  Soft  and  hard  wheats. 

16.  Removing  the  stamens  from  the  blossom. 

17.  Breaking  of  pollen  sacks. 

18.  Removing  undesirable  flowers. 

19.  Growing  the  first  seed  from  hybrids. 

20.  Emasculating  and  cross-pollinating  wheat  flowers. 

21.  Variation  in  size  of  head. 

22.  Map  showing  the  distribution  of  different  types  of  wheat  within  the  United  States. 

23.  Plowing  wheat  land. 

24.  Disking  wheat  land. 

25.  Disking  cornstalk  ground  for  wheat. 

26.  Liming  land. 

27.  Testing  seed  wheat. 

28.  Germination  of  plump  and  shrunken  seed  wheat 

29.  Drilling  wheat. 

30.  Furrow  method  of  irrigating  wheat. 

31.  Effect  of  irrigation  on  the  composition  of  wheat. 

32.  Appearance  of  grains  of  different  hardness  and  composition. 

33.  Self-binders  at  work. 

34.  Combined  harvester  operated  by  horses. 

35.  Combined  harvester  operated  with  steam  power. 

36.  Cradling  wheat. 

(19) 


20 

37.  A  primitive  method  of  thrashing  wheat. 

38.  Modern  thrashing  outfit. 

39.  Sacked  wheat  stored  in  the  open. 

40.  A  Chicago  grain  elevator. 

41.  A  Canadian  grain  elevator. 

42.  Grain  elevator,  Manchester,  England. 

43.  Wheat  heads  and  straw,  showing  rust. 

44.  Effect  of  rust  on  wheat  grains. 

45.  Shrinking  of  grains  due  to  rust. 

46.  Table  of  production  in  various  countries.  ' 

REFERENCES. 

1.  The  Cereals  in  America.     By  T.  F.  Hunt. 

2.  The  Book  of  Wheat.     By  P.  T.  Dondlinger. 

3.  The  Culture  of  Winter  Wheat  in  the  Eastern  United  States.    U.  S.  Dept.  Agr. 

Farmers'  Bui.  596. 

4.  Winter  Wheat  Varieties  for  the  Eastern  United  States.     U.  S.  Dept.  Agr.  Farmers' 

Bui.  616. 

5.  Winter  Wheat  in  the  Great  Plains  Area.     U.  S.  Dept.  Agr.  Bui.  595. 

6.  Growing  Hard  Spring  Wheat.     U.  S.  Dept.  Agr.  Farmers'  Bui.  678. 

7.  Spring  Wheat  in  the  Great  Plains  Area.     Relation  of  Cultural  Methods  to  Pro- 

duction.    U.  S.  Dept.  Agr.  Bui.  214. 

8.  Varieties  of  Hard  Spring  Wheat.    U.  S.  Dept.  Agr.  Farmers'  Bui.  680. 

9.  Wheat  Experiments.     Ohio  Sta.  Bui.  298. 

10.  Insects  Destructive  to  Grain  and  Grain  Products  Stored  in  Bins  and  Granaries. 

Kansas  Station  Circ.  47. 

11.  The  Change  in  Weight  of  Grain  in  Arid  Regions  During  Storage.     Utah  Station 

Bui.  130. 

12.  Chinch  Bug.    U.  S.  Dept.  Agr.  Farmer's  Bui.  657. 

13.  Hessian  Fly.     U.  S.  Dept.  Agr.  Farmers'  Bui.  640. 

14.  Statistics  of  Grain  Crops.     U.  S.  Dept.  Agr.  Yearbook  1916. 

15.  Smuts  of  Wheat,  Oats,  Barley,  and  Corn.    U.  S.  Dept.  Agr.  Farmers'  Bui.  507. 


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